drivers/watchdog/w83627hf_wdt.c

   1 /*
   2  *      w83627hf/thf WDT driver
   3  *
   4  *      (c) Copyright 2013 Guenter Roeck
   5  *              converted to watchdog infrastructure
   6  *
   7  *      (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
   8  *              added support for W83627THF.
   9  *
  10  *      (c) Copyright 2003,2007 Pádraig Brady <P@draigBrady.com>
  11  *
  12  *      Based on advantechwdt.c which is based on wdt.c.
  13  *      Original copyright messages:
  14  *
  15  *      (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
  16  *
  17  *      (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
  18  *                                              All Rights Reserved.
  19  *
  20  *      This program is free software; you can redistribute it and/or
  21  *      modify it under the terms of the GNU General Public License
  22  *      as published by the Free Software Foundation; either version
  23  *      2 of the License, or (at your option) any later version.
  24  *
  25  *      Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
  26  *      warranty for any of this software. This material is provided
  27  *      "AS-IS" and at no charge.
  28  *
  29  *      (c) Copyright 1995    Alan Cox <alan@lxorguk.ukuu.org.uk>
  30  */
  31
  32 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  33
  34 #include <linux/module.h>
  35 #include <linux/moduleparam.h>
  36 #include <linux/types.h>
  37 #include <linux/watchdog.h>
  38 #include <linux/ioport.h>
  39 #include <linux/init.h>
  40 #include <linux/io.h>
  41
  42 #define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT"
  43 #define WATCHDOG_TIMEOUT 60             /* 60 sec default timeout */
  44
  45 static int wdt_io;
  46 static int cr_wdt_timeout;      /* WDT timeout register */
  47 static int cr_wdt_control;      /* WDT control register */
  48 static int cr_wdt_csr;          /* WDT control & status register */
  49
  50 enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
  51              w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg, w83627dhg_p,
  52              w83667hg_b, nct6775, nct6776, nct6779, nct6791, nct6792, nct6793,
  53              nct6795, nct6102 };
  54
  55 static int timeout;                     /* in seconds */
  56 module_param(timeout, int, 0);
  57 MODULE_PARM_DESC(timeout,
  58                 "Watchdog timeout in seconds. 1 <= timeout <= 255, default="
  59                                 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
  60
  61 static bool nowayout = WATCHDOG_NOWAYOUT;
  62 module_param(nowayout, bool, 0);
  63 MODULE_PARM_DESC(nowayout,
  64                 "Watchdog cannot be stopped once started (default="
  65                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
  66
  67 static int early_disable;
  68 module_param(early_disable, int, 0);
  69 MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
  70
  71 /*
  72  *      Kernel methods.
  73  */
  74
  75 #define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
  76 #define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
  77                                                         (same as EFER) */
  78 #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
  79
  80 #define W83627HF_LD_WDT         0x08
  81
  82 #define W83627HF_ID             0x52
  83 #define W83627S_ID              0x59
  84 #define W83697HF_ID             0x60
  85 #define W83697UG_ID             0x68
  86 #define W83637HF_ID             0x70
  87 #define W83627THF_ID            0x82
  88 #define W83687THF_ID            0x85
  89 #define W83627EHF_ID            0x88
  90 #define W83627DHG_ID            0xa0
  91 #define W83627UHG_ID            0xa2
  92 #define W83667HG_ID             0xa5
  93 #define W83627DHG_P_ID          0xb0
  94 #define W83667HG_B_ID           0xb3
  95 #define NCT6775_ID              0xb4
  96 #define NCT6776_ID              0xc3
  97 #define NCT6102_ID              0xc4
  98 #define NCT6779_ID              0xc5
  99 #define NCT6791_ID              0xc8
 100 #define NCT6792_ID              0xc9
 101 #define NCT6793_ID              0xd1
 102 #define NCT6795_ID              0xd3
 103
 104 #define W83627HF_WDT_TIMEOUT    0xf6
 105 #define W83697HF_WDT_TIMEOUT    0xf4
 106 #define NCT6102D_WDT_TIMEOUT    0xf1
 107
 108 #define W83627HF_WDT_CONTROL    0xf5
 109 #define W83697HF_WDT_CONTROL    0xf3
 110 #define NCT6102D_WDT_CONTROL    0xf0
 111
 112 #define W836X7HF_WDT_CSR        0xf7
 113 #define NCT6102D_WDT_CSR        0xf2
 114
 115 static void superio_outb(int reg, int val)
 116 {
 117         outb(reg, WDT_EFER);
 118         outb(val, WDT_EFDR);
 119 }
 120
 121 static inline int superio_inb(int reg)
 122 {
 123         outb(reg, WDT_EFER);
 124         return inb(WDT_EFDR);
 125 }
 126
 127 static int superio_enter(void)
 128 {
 129         if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
 130                 return -EBUSY;
 131
 132         outb_p(0x87, WDT_EFER); /* Enter extended function mode */
 133         outb_p(0x87, WDT_EFER); /* Again according to manual */
 134
 135         return 0;
 136 }
 137
 138 static void superio_select(int ld)
 139 {
 140         superio_outb(0x07, ld);
 141 }
 142
 143 static void superio_exit(void)
 144 {
 145         outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
 146         release_region(wdt_io, 2);
 147 }
 148
 149 static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
 150 {
 151         int ret;
 152         unsigned char t;
 153
 154         ret = superio_enter();
 155         if (ret)
 156                 return ret;
 157
 158         superio_select(W83627HF_LD_WDT);
 159
 160         /* set CR30 bit 0 to activate GPIO2 */
 161         t = superio_inb(0x30);
 162         if (!(t & 0x01))
 163                 superio_outb(0x30, t | 0x01);
 164
 165         switch (chip) {
 166         case w83627hf:
 167         case w83627s:
 168                 t = superio_inb(0x2B) & ~0x10;
 169                 superio_outb(0x2B, t); /* set GPIO24 to WDT0 */
 170                 break;
 171         case w83697hf:
 172                 /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
 173                 t = superio_inb(0x29) & ~0x60;
 174                 t |= 0x20;
 175                 superio_outb(0x29, t);
 176                 break;
 177         case w83697ug:
 178                 /* Set pin 118 to WDTO# mode */
 179                 t = superio_inb(0x2b) & ~0x04;
 180                 superio_outb(0x2b, t);
 181                 break;
 182         case w83627thf:
 183                 t = (superio_inb(0x2B) & ~0x08) | 0x04;
 184                 superio_outb(0x2B, t); /* set GPIO3 to WDT0 */
 185                 break;
 186         case w83627dhg:
 187         case w83627dhg_p:
 188                 t = superio_inb(0x2D) & ~0x01; /* PIN77 -> WDT0# */
 189                 superio_outb(0x2D, t); /* set GPIO5 to WDT0 */
 190                 t = superio_inb(cr_wdt_control);
 191                 t |= 0x02;      /* enable the WDTO# output low pulse
 192                                  * to the KBRST# pin */
 193                 superio_outb(cr_wdt_control, t);
 194                 break;
 195         case w83637hf:
 196                 break;
 197         case w83687thf:
 198                 t = superio_inb(0x2C) & ~0x80; /* PIN47 -> WDT0# */
 199                 superio_outb(0x2C, t);
 200                 break;
 201         case w83627ehf:
 202         case w83627uhg:
 203         case w83667hg:
 204         case w83667hg_b:
 205         case nct6775:
 206         case nct6776:
 207         case nct6779:
 208         case nct6791:
 209         case nct6792:
 210         case nct6793:
 211         case nct6795:
 212         case nct6102:
 213                 /*
 214                  * These chips have a fixed WDTO# output pin (W83627UHG),
 215                  * or support more than one WDTO# output pin.
 216                  * Don't touch its configuration, and hope the BIOS
 217                  * does the right thing.
 218                  */
 219                 t = superio_inb(cr_wdt_control);
 220                 t |= 0x02;      /* enable the WDTO# output low pulse
 221                                  * to the KBRST# pin */
 222                 superio_outb(cr_wdt_control, t);
 223                 break;
 224         default:
 225                 break;
 226         }
 227
 228         t = superio_inb(cr_wdt_timeout);
 229         if (t != 0) {
 230                 if (early_disable) {
 231                         pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
 232                         superio_outb(cr_wdt_timeout, 0);
 233                 } else {
 234                         pr_info("Watchdog already running. Resetting timeout to %d sec\n",
 235                                 wdog->timeout);
 236                         superio_outb(cr_wdt_timeout, wdog->timeout);
 237                 }
 238         }
 239
 240         /* set second mode & disable keyboard turning off watchdog */
 241         t = superio_inb(cr_wdt_control) & ~0x0C;
 242         superio_outb(cr_wdt_control, t);
 243
 244         /* reset trigger, disable keyboard & mouse turning off watchdog */
 245         t = superio_inb(cr_wdt_csr) & ~0xD0;
 246         superio_outb(cr_wdt_csr, t);
 247
 248         superio_exit();
 249
 250         return 0;
 251 }
 252
 253 static int wdt_set_time(unsigned int timeout)
 254 {
 255         int ret;
 256
 257         ret = superio_enter();
 258         if (ret)
 259                 return ret;
 260
 261         superio_select(W83627HF_LD_WDT);
 262         superio_outb(cr_wdt_timeout, timeout);
 263         superio_exit();
 264
 265         return 0;
 266 }
 267
 268 static int wdt_start(struct watchdog_device *wdog)
 269 {
 270         return wdt_set_time(wdog->timeout);
 271 }
 272
 273 static int wdt_stop(struct watchdog_device *wdog)
 274 {
 275         return wdt_set_time(0);
 276 }
 277
 278 static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
 279 {
 280         wdog->timeout = timeout;
 281
 282         return 0;
 283 }
 284
 285 static unsigned int wdt_get_time(struct watchdog_device *wdog)
 286 {
 287         unsigned int timeleft;
 288         int ret;
 289
 290         ret = superio_enter();
 291         if (ret)
 292                 return 0;
 293
 294         superio_select(W83627HF_LD_WDT);
 295         timeleft = superio_inb(cr_wdt_timeout);
 296         superio_exit();
 297
 298         return timeleft;
 299 }
 300
 301 /*
 302  *      Kernel Interfaces
 303  */
 304
 305 static const struct watchdog_info wdt_info = {
 306         .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
 307         .identity = "W83627HF Watchdog",
 308 };
 309
 310 static const struct watchdog_ops wdt_ops = {
 311         .owner = THIS_MODULE,
 312         .start = wdt_start,
 313         .stop = wdt_stop,
 314         .set_timeout = wdt_set_timeout,
 315         .get_timeleft = wdt_get_time,
 316 };
 317
 318 static struct watchdog_device wdt_dev = {
 319         .info = &wdt_info,
 320         .ops = &wdt_ops,
 321         .timeout = WATCHDOG_TIMEOUT,
 322         .min_timeout = 1,
 323         .max_timeout = 255,
 324 };
 325
 326 /*
 327  *      The WDT needs to learn about soft shutdowns in order to
 328  *      turn the timebomb registers off.
 329  */
 330
 331 static int wdt_find(int addr)
 332 {
 333         u8 val;
 334         int ret;
 335
 336         cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
 337         cr_wdt_control = W83627HF_WDT_CONTROL;
 338         cr_wdt_csr = W836X7HF_WDT_CSR;
 339
 340         ret = superio_enter();
 341         if (ret)
 342                 return ret;
 343         superio_select(W83627HF_LD_WDT);
 344         val = superio_inb(0x20);
 345         switch (val) {
 346         case W83627HF_ID:
 347                 ret = w83627hf;
 348                 break;
 349         case W83627S_ID:
 350                 ret = w83627s;
 351                 break;
 352         case W83697HF_ID:
 353                 ret = w83697hf;
 354                 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
 355                 cr_wdt_control = W83697HF_WDT_CONTROL;
 356                 break;
 357         case W83697UG_ID:
 358                 ret = w83697ug;
 359                 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
 360                 cr_wdt_control = W83697HF_WDT_CONTROL;
 361                 break;
 362         case W83637HF_ID:
 363                 ret = w83637hf;
 364                 break;
 365         case W83627THF_ID:
 366                 ret = w83627thf;
 367                 break;
 368         case W83687THF_ID:
 369                 ret = w83687thf;
 370                 break;
 371         case W83627EHF_ID:
 372                 ret = w83627ehf;
 373                 break;
 374         case W83627DHG_ID:
 375                 ret = w83627dhg;
 376                 break;
 377         case W83627DHG_P_ID:
 378                 ret = w83627dhg_p;
 379                 break;
 380         case W83627UHG_ID:
 381                 ret = w83627uhg;
 382                 break;
 383         case W83667HG_ID:
 384                 ret = w83667hg;
 385                 break;
 386         case W83667HG_B_ID:
 387                 ret = w83667hg_b;
 388                 break;
 389         case NCT6775_ID:
 390                 ret = nct6775;
 391                 break;
 392         case NCT6776_ID:
 393                 ret = nct6776;
 394                 break;
 395         case NCT6779_ID:
 396                 ret = nct6779;
 397                 break;
 398         case NCT6791_ID:
 399                 ret = nct6791;
 400                 break;
 401         case NCT6792_ID:
 402                 ret = nct6792;
 403                 break;
 404         case NCT6793_ID:
 405                 ret = nct6793;
 406                 break;
 407         case NCT6795_ID:
 408                 ret = nct6795;
 409                 break;
 410         case NCT6102_ID:
 411                 ret = nct6102;
 412                 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
 413                 cr_wdt_control = NCT6102D_WDT_CONTROL;
 414                 cr_wdt_csr = NCT6102D_WDT_CSR;
 415                 break;
 416         case 0xff:
 417                 ret = -ENODEV;
 418                 break;
 419         default:
 420                 ret = -ENODEV;
 421                 pr_err("Unsupported chip ID: 0x%02x\n", val);
 422                 break;
 423         }
 424         superio_exit();
 425         return ret;
 426 }
 427
 428 static int __init wdt_init(void)
 429 {
 430         int ret;
 431         int chip;
 432         static const char * const chip_name[] = {
 433                 "W83627HF",
 434                 "W83627S",
 435                 "W83697HF",
 436                 "W83697UG",
 437                 "W83637HF",
 438                 "W83627THF",
 439                 "W83687THF",
 440                 "W83627EHF",
 441                 "W83627DHG",
 442                 "W83627UHG",
 443                 "W83667HG",
 444                 "W83667DHG-P",
 445                 "W83667HG-B",
 446                 "NCT6775",
 447                 "NCT6776",
 448                 "NCT6779",
 449                 "NCT6791",
 450                 "NCT6792",
 451                 "NCT6793",
 452                 "NCT6795",
 453                 "NCT6102",
 454         };
 455
 456         wdt_io = 0x2e;
 457         chip = wdt_find(0x2e);
 458         if (chip < 0) {
 459                 wdt_io = 0x4e;
 460                 chip = wdt_find(0x4e);
 461                 if (chip < 0)
 462                         return chip;
 463         }
 464
 465         pr_info("WDT driver for %s Super I/O chip initialising\n",
 466                 chip_name[chip]);
 467
 468         watchdog_init_timeout(&wdt_dev, timeout, NULL);
 469         watchdog_set_nowayout(&wdt_dev, nowayout);
 470         watchdog_stop_on_reboot(&wdt_dev);
 471
 472         ret = w83627hf_init(&wdt_dev, chip);
 473         if (ret) {
 474                 pr_err("failed to initialize watchdog (err=%d)\n", ret);
 475                 return ret;
 476         }
 477
 478         ret = watchdog_register_device(&wdt_dev);
 479         if (ret)
 480                 return ret;
 481
 482         pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
 483                 wdt_dev.timeout, nowayout);
 484
 485         return ret;
 486 }
 487
 488 static void __exit wdt_exit(void)
 489 {
 490         watchdog_unregister_device(&wdt_dev);
 491 }
 492
 493 module_init(wdt_init);
 494 module_exit(wdt_exit);
 495
 496 MODULE_LICENSE("GPL");
 497 MODULE_AUTHOR("Pádraig  Brady <P@draigBrady.com>");
 498 MODULE_DESCRIPTION("w83627hf/thf WDT driver");